<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>

    //浮点数直接运算，结果不一定是正确的;
    var test1=0.1+0.2;
    console.log(test1);//0.30000000000000004
    var test2=(0.1*10+0.2*10)/10;
    console.log(test2);//0.3

    //NaN
    console.log(10-"zhuanbang");//NaN   Not a Number
    var NaNVal=10-"zhuanbang";
    console.log(typeof NaNVal);//number NaN是number类型
    console.log(NaNVal==NaNVal);//false

    //isNaN
    var age=25;
    var ageError=25-"男";
    console.log(isNaN(age));//false       age这个值不是一个数，对不对？      -> 不对  ->false
    console.log(isNaN(ageError));//true   ageError这个值不是一个数，对不对？ -> 对    ->true

    //num1是多少分
    var num1="564878.12415ssss";

    var min1=Number(num1)/60,
        min2=parseInt(num1)/60,
        min3=parseFloat(num1)/60;
    console.log(min1,min2,min3);

    var targetMin=parseInt(min2);
    console.log(targetMin);//9414秒
</script>
</body>
</html>